Ms. McGrath is an environmental scientist with over 20 years of experience in risk assessment, specializing in bioavailability of sediment-associated contaminants to the aquatic community, water and sediment criteria development and fate of contaminants through wastewater treatment processes. Ms. McGrath has participated in developing and reviewing existing criteria for non-polar organics with a focus on hydrocarbons for industrial and governmental clients. She has extensive experience in understanding the framework for how various sediment criteria for single polycyclic aromatic hydrocarbons and total petroleum hydrocarbons were developed. She has designed laboratory and field sampling programs to determine fate of several pesticides through wastewater treatment facilities for use in risk assessment during the registration/re-registration process.

Ms. McGrath was a co-author on the original research for the target lipid model (TLM), a framework for deriving water and sediment criteria for mixtures of non-polar chemicals that act via narcosis, such as hydrocarbons. The TLM has been adopted by the U.S. EPA and other international environmental agencies for use in deriving sediment criteria for the protection of benthic invertebrates from exposure to mixtures of polycyclic aromatic hydrocarbons. Ms. McGrath has published several subsequent manuscripts on the TLM model refinements and its application to various environmental media. She was also involved in the development of PETROTOX which utilizes the TLM framework for predicting the toxicity of various petroleum products that is being implemented under REACH guidance.

Ms. McGrath has helped numerous industrial clients in the food and beverage, pharmaceutical and chemical manufacturing sectors use treatability testing to optimize removals of contaminants through treatment facilities, determine best treatment strategy for meeting discharge limits, determine if facilities have sufficient capabilities to receive additional nutrient or organic load and maintain current treatment objectives and help clients determine cause and solutions for plant upsets. On the behalf of clients, she has presented to the U.S. EPA the value of treatability testing and how the results can be used in risk assessment.

McGrath JA, Paquin PR, Di Toro DM. Use of the SEM and AVS Approach in Predicting Metal Toxicity in Sediments.. Fact Sheet on Environmental Risk Assessment, Published by the International Council on Mining and Metals (ICMM). 2002.

McGrath J. Evaluation of PAH and TPH Guidelines for the Protection of Benthic Invertebrates. Poster presentation, 9th International Conference on Remediation and Management of Contaminated Sediments, New Orleans, LA 2017.

Professional Affiliations

Project Experience

Conducted comprehensive review of sediment guidelines for single PAH and TPH for protection of benthic invertebrates. Evaluated data, approach and reliability of the method to determine appropriateness and value in applying for use in identifying potential risk.

Managed an extensive review of water-only toxicity data for single compound petroleum hydrocarbons. Compiled a high quality database for use in developing protection values for use in risk assessment of petroleum products.

Managed an extensive review of effect of pressure on toxicity of hydrocarbon gases. Determined basis for assuming that hydrocarbon gases behave as narcotics. Developed an application factor to the target lipid model framework to account for effect of pressure on toxicity of these light weight gases.

Managed a laboratory treatability effort on a refinery wastewater which contained elevated levels of arsenic and ammonia-nitrogen. The optimum conditions for arsenic removal were identified. Also investigated if the wastewater could be discharged to the local POTW without disrupting the plant’s ability to achieve complete nitrification and continue to meet discharge limits.

Managed a laboratory treatability effort simulating the fate of a pesticide synergist through wastewater treatment processes. Processes included conventional and advanced treatment systems. Data were used in the re-registration process.

Conducted a pilot scale study on removal of carbamates through drinking conventional and advanced drinking water processes. Data were used in the re-registration process.